The likelihood that the U.S. will see a catastrophic earthquake within the next 30 years is very high — and it’s not just the West Coast that’s at risk, experts say.
Seismologists have long warned that the U.S. is “overdue” for an earthquake, because a catastrophic one has not occurred in the U.S. since about 1989, when the Loma Prieta earthquake killed at least 63 people in California, said Robert Yeats, a geology professor at Oregon State University. The most destructive earthquake the U.S. has ever seen was the 7.9-magnitude “Great San Francisco Earthquake of 1906,” which killed an estimated 3,000 people, according to the agency. As more years have passed without earthquakes, pressure has built up along certain fault lines as tectonic plates try to shift, including in the Pacific Northwest and California, Yeats said.
Earthquakes, which occur when two Earth surfaces move against each other, are typically difficult to predict and impossible to prevent. But the U.S. Geological Survey (USGS) maps out high-risk zones based on seismic and geologic data that take into account when and where earthquakes occurred in the past, among other measures that help them predict future events, according to Morgan Moschetti, a USGS research geophysicist. See which areas have the highest potential for an earthquake below.
California is famous for being an earthquake hot zone. As shown on the map above, most of the state and its neighbors to the north carry the highest risk for earthquakes. California, a highly seismically active area, has more than 300 fault lines crossing the state. Particularly at risk is the southern part of the San Andreas fault, which runs close to Los Angeles and has remained quiet since a magnitude 7.9 earthquake in 1857, meaning a lot of pressure has built up along that part of the fault line, Yeats said. According to Moschetti, Southern California, Los Angeles and the San Francisco Bay Area are most at risk in the coming years.
The Pacific Northwest, located along the Cascadia subduction zone, a fault that runs from Vancouver Island to northern California, is bracing itself for an earthquake as pressure has built up in the zone since the 1700s, Yeats said. He said the eventual earthquake could measure at a magnitude of 9, and could be potentially comparable to the San Sixto earthquake, which hit Mexico in 1787 with an estimated magnitude of 8.6.
“The thickness and size of the plates means that when it…